The invention relates to a process for producing a distributor plate for an electrochemical system and also a distributor plate for an electrochemical system.
Fuel cells are electrochemical energy converters in which reaction gases, for example hydrogen (H2), (as fuel) and oxygen (O2) are converted into water (H2O), i.e. chemical energy is converted into electric energy and heat. In the case of PEM fuel cells (polymer electrolyte membrane fuel cells), a plurality of fuel cells are usually positioned on top of one another to form a fuel cell stack. The reaction gases hydrogen and the oxygen from the air and also cooling liquid are conveyed via a media distributor structure into the fuel cells. This media distributor structure is configured either as channel or as electrically conductive porous layer (foam). The channel media distributor structure and the foam media distributor structure with the seal are parts of the bipolar plate of a PEM fuel cell. Apart from the membrane, the bipolar plate is a very costly component of the fuel cell and in the current state of manufacturing technology makes up from 30 to 45% of the fuel cell stack costs. The reasons are the surfaces provided with fine groove structures together with a very low residual wall thickness of the bipolar plate. At the same time, the material of the bipolar plate has to withstand an active and very demanding chemical environment without corrosion or membrane-damaging ion leaching occurring. These far-reaching specifications which the bipolar plates and their materials have to meet lead to the use of very expensive materials and also complicated processing methods which keep the costs of the bipolar plates at a permanently high level. In this respect, the development of alternative and more efficient production methods in the production of the bipolar plates is of great importance.